1. Field of Invention
The present invention relates to radio resource allocation methods and apparatus.
2. Description of the Related Art
With the advent with another generation of wireless networks known as Universal Mobile Telephone Systems (UMTS) based on wide band code-division multiple access (W/CDMA) techniques, the allocation of radio resources needs to be structured to cope with both the dynamically changing quality of service (QoS) and with the different classes of service (eg real time and non-real time) in a more efficient way.
In a mobile telephone system, communication is effected through a series of nodes eg base stations. Each node receives data from several sources eg mobile phone and needs to transmit that data onwards. The radio resource capacity for each node is limited by such factors as the available transmission power and code sequences. As a result, there will sometimes be more requests for transmission of data through a node than its available capacity. While each request to the node to transmit data will have a minimum quality of service requirement, the quality of service required will vary with time during any particular transmission due to such factors as the speed of a mobile telephone through an environment and internal or external interference.
Requests to transmit data between a mobile phone and a base station are sent over a dedicated control channel (DCCH) while the actual data to be transmitted is sent over a dedicated traffic channel (DTCH).
It is an object of the present invention to provide an improved radio resource allocation method and apparatus.
According to the present invention there is provided a radio resource allocation method for allocating radio resources for transmission of signals along one or more channels between two nodes comprising the step of monitoring the different requests for transmission of signals between said nodes, dividing the requests into two classes, a first class for real time requirements and a second class for non-real time requirements, extracting from each request a first parameter representing the data rate (Rb) requirement and a second parameter representing the bit energy to noise ratio (Eb/No) requirement prioritising the requests in order based on a predetermined set of rules, and allocating available channels to meet the request in order of priority.
According to the present invention there is further provided radio resource allocation apparatus for allocating radio resources for transmission of signals along a plurality of channels to and from a node, the node comprising a transmitter/receiver for transmitting and receiving signals to and from the node and a channel selection device for selecting the channels along which different signal transmissions are to be routed, and a channel allocation device for controlling the allocation of channels by the channel selection device, the channel allocation device comprising first means responsive to incoming signal transmissions passing through the node to produce a data rate signal, a bit energy to noise power ratio signal and a classification signal, second means responsive to the output of the first means to generate a maximum load parameter signal and third means responsive to an output from the channel selection device providing channel status indications and to the output of the first and second means to process the received signals in accordance with a predetermined algorithm and to feed the channel selection device with channel selection signals accordingly.